Relay



Aug. 7, 1928. 1,679,761

. D. c. BETrlsoN D. BQ ttf-San, invento/ attorney Aug. 7, 1928, Y

- D. c. BETTlsoN RELAY 'Fi-led Aug. 9, 1926 2 Sheets-Sheet 2 Il /z Y f4 42 "/3 /3 f Y w /4 47 4 J 4 7:11 33. 38. V45 f5 \35 .as

afloran i adjustments of the Patented Aug. 7, 1928.

UNIT su STAT as PAT ENT nAvIDe. B-ErrIsoiv, or` OMAHA, Ninna/estira.4

RELAY.

Application mea` migust 9, 1926. serial Nofiaaasv.

invention relates to electric relays,

relays operated by direct curparticular object of myinventionl is to pro` vide a novel method and means `for supporting thev relay armature, wherebyv said supporting means will not be subject to wear,`

orliability to become inoperative by sticking of parts together by corrosiomor by welding of parts together by fusion,re'sulting from lightning or other high-tension electrical discharges `through the instrument, and

whereby adjustments may bemade of the 'polar gap or normal distance atwhich the armature'isheld from the pole-pieces of the eleetromagnets. A further object of my invention is to provide iii relays of the class mentioned a novel construction of the con,-

`tacts wlierebysaid contacts may be readilyadjusted to a desired gapwhen in open position, and to the desired contact-pressure when in closed position, the Yadjusting Vmeans loeinov Quch that the faces of the stationary contctis may be accurately alined with the faces of the movablecontacts,` and a plurality of sets of the contacts be alined or. ad-

justed to close and open their lrespectivey circuits simultaneously, and whereby said contacts 'involve no un-` controlled deformations of the parts, such that spontaneous changes of Athe adjust/-` nient may subsequently occur by reason of a tendency oi' the deformed parts to `resume their original formation.

Inthe accompanying drawings Fig. 1 is a side view, partially brokenaway, of va relayA embodying my invention, Fig. 2 is a diagrammatic view illustrating the movement ofthe armature from open to closed position about the quasi-ulcrum formed by the flexible armature-supports, Fig. Sis a partial rear view of armature supports and associated parts, Fig. 4t is a detail vertical section on the line of Fig. 1, showing the contacts in front elevation, Fig. 5 isa detail bottom view ,of one of the adjustableV contacts, Fig.` 6 isl a side view of the same, Fig. 7 is a detail front view of one of the a sectional view the types used tor railway Isig` armature-supportingspringaand Fig. 8 is l of 4the saine on the line 8*-8 ofFim. y j

` 'In carrying outmy inventionaccording to.

the illustrated'embodiment thereol provide a relay of which the general construction and operation vis substantially that ycommonly mie-,761. ri-ics employed for direct-current relays for railway signalling, three being an clectromagnet formed by a pair of coils lO-hav'ing` a connecting yokell'at the upper endsof the coilcores,t he lower ends of the Cores extending through a base-plate v12 and carrying the pole-pieces 13,.beneath which is themovable larmature 14. The armature and thecontact fingers l15` carried thereby, together with the stationary and movable circuit-controlling contacts and adjustingmeans are inclosed by a glass casing 16 which fits within a marginalv flange yof 'the base 12, a similarly flanged bottom-plate 17 completing the'in-` closure, and said bottom-plate'being secured to the plate 12 by corner-posts 1S.V A. lateral extension ofthe yolte 11 carries the binding-posts 19which forni-thecoil terminals for connection withthe'external controlling-circuit. Upon therear portion ofthe base 12 are-mounted the binding-posts 2O from which the Yflexible conductors 21 are eXteiidedto theiigeils 15,a`nd upon the" front portion of the baseare mounted the binding-posts 22 and 23 lwhich carry the front and back stationaryv contacts-respectivelyff Inthe lusual construction .ofrelays of this class7 the armature is supported byfpivotally V QU i mounting the same between a pair'of pivot- VVpins'alined uponfan axis about Vwl'iich'the armature moves, the latter being swung up towardtlie pole-pieces when the electro-inagnet `is sufficiently'energized, and ydropping away from the pole-pieces by 'gravity when the energization ofthe electromagnet reduced below, a determined 'minimumin railway signalling mechanism under control of relays it is the invariable practicejto have the signals placed at and held in clear. posiy tion when the electromagnetslof thecontrollingfrel'ay attain a certain minimum ener? gizat'ion, and tofhave the signals nieve `to danger position by the openingl or `closing of circuits effected by the gravitational movement of the relay armature resulting freni reduced.energization of the electromagnets.

Obviously, any defect of the armature support, such `sticking of the pivot-pins by corrosion, or by v'fusion from lightning discharges, or by excessive friction at'the pivots due to bending or other deformations of the pins, may cause the armature to remain in closed position and thus to show a clear signal when the proper indication of the signal should be danger; and in practice it is found that suchfalse signal indications are quite often caused by failure of a relay dueto defects of the pivotal supports of the armature such as above mentioned. Y

The foregoing difficulties and liabilities to failure are avoided in my improved relay, by supporting` the armature as follows: From the rear portion of the base-plate l2, adjacent to the binding-posts 20, a bracket 24 is extended downwardly as shown, and

" to the horizontal lower portion of said bracket are secured the lower 'ends of `a pair ofv flat stripsA 25 ofr spring material such as phosphor-bronze. Saidy spring strips are secured to the bracket by means of small bolts 2G which pass through slots 27 in the strips, the slots permitting -a slight vertical adjustment lof the strips relative to the bracket. The strips extend substantially vertically, and theupper ends thereof engage theV ends of Alugs 28 e-xtended rearwardly from the armature 14, and screws 29 are extended through holes 30 in said upper ends of the strips to fixedly secure the same to said lugs 28, and thereby support the armature. The flexible armattire-supporting strips 25 are thus disposed in a plane substantially parallel with a plane passing through the axes vof the magnet poles, or, with reference to eithervpole alone, substantially parallel with the line of magnetic trac,- tion or the direction in` which the magnetic traction is exerted upon the' armature; and the strips are spaced laterally from the line of traction sufficiently to enable movement of the armature from and toward the `polepieces by laterall bending of the strips, gDuring such-movements of thearmature the lateral deflection of the spring stripsis dis` tributed over a vconsiderable portion of their length, Abeing greatest adjoining thek fixed lower ends thereof and decreasing toward the upper ends to vwhich kthe armature is Secured, andthe resultingmovement of the armature is substantially the same thatv would occur ifithe stripsv were rigid and inflexible, and were pivoted to swing about a fixed horizontal axis located near their lower ends. The action above mentioned will be clearly apparent from the diagrammatic representation of the parts in Fig. 2, wherein the circle 3l indicates the hypothetical or quasi-fulcrum about which the pivotal movement occurs, the vvertical line 32 indicates the line of traction, and the arrows indicate the paths of movement, respectively, of a point`32 at the'center of the armature, and a point 33 lat the front end ofthe rigid extension of the armature formed by the contact-lingers 15.Y t willV` be seen'that a point 345 on the rear edge of the armature, at tl e upper'end' of the support-strips and directly above the quasi-fulcrum 3l, will have substantially no vertical movement but can move only upon an almosthorizontal arc, although the movement of the point 32 at the center of thearmature has a vertical component substantially equal to the horizontal composure producedj at the point willbe proportioned to the lmagnetic traction at the point 32 inversely as the distances of said points 33Y and 32 from the point and that this result cannot be attained by supportin'gthe armature upon flat springs extending transversely to the axis of magnetic traction, Vbecause in such case the lateral flexure of the springs would permit movement of the p-oint 34- upwardly when the upward movement ofthe point 33 was resisted..

It will beapparent that by the described flexible armature-supjiorting means,l gravitational movement vof the armature to the lowered position thereof, when the pull of the electromagnet falls below the determined minimum, cannot be prevented'by sticking, corrosion, fusing or any similar derangement of the armature-supporting means, and that should the springs be brokenor destroyed the armature would'drop down in such a. manner that thecontrolled signals would be set to danger' indication. It will also bc seen that adjustment of the air-gap or normal space between the armature and polepieces may be effected when desired, by loosening the attaching bolts which pass through .the slots 27 in the lower portions of the tioned In the-illustrated construction, two

of thecontact-fingers are provided, although any desired number of the fingers may be used, according to the particular use for which the relay is intended, relays of this class being used for various purposes requiring from two to six of the contactfingers. OnV each finger a vback-contact is formed by a spring 36 secured to the lower side of the finger and'adapted to engage the fixed back-contact 37 carried by a loop or lbinding-post 23.A A front-contact for each Cil finger is `formed by aspring 38 which is preferably a .straight-j fiat pieceA of metal extending diagonallygupward and forward from` the finger, the latter being formed intermediate its ends with an angular portion 39 so proportioned and arranged lthat the spring will be held at the desired diagonal` position when the lower end portion thereof.

is secured against the flat side .of said angular portion 39, A smallbolt 40 is employed. `for securing both of the springs 36 and 38 to thefnger. The contacts "41 which arev thesprings 38 are carried engageablc by the binding-posts `22, and are adjustably con- `nected therewith as follows: Each contact 4l is secured to the lower portion ofy a U -shaped strip 42 of resilient metal, andthe upper. portion or leg of the U-strip is secured by a. screw ,43 to the lower end `of the bindingpost which extends through the plate The material usedinsaid strip 42should be a good electrical conductor, such as brass or bronze, and sulliciently resilient toallow the desired adjustments or variation 1n position of the contact 41 by spreading or drawing toward each other the ends .or legs of the U-strip. The adjustment is effected by means of a pair of screws 44 which'pass through openings in one leg and into threaded openings in the other leg of the AU-strip adjacent lto the open end of the U.

By tightening or loosening one of the screws 44 without changing the position of the other, the Contact 41 may be slightly tilted laterally whereby to accurately aline the face thereof with the end-face of the respective contact-spring 38. By equal adjustments of both screws 44 the position of the Contact 4l may be varied vto increase or decrease the gap at open position, to vary the contact-pressure at closed position, and to place a plurality of the contacts in such relation to their respective contact-springs 38 that the controlled circuits will be opened or closed simultaneously.

In relays of the ordinary types, .wherein adjustments of thel contacts are effected by bending the contact-springs carried by the armature or contact-fingers, the adjustments are not accurately maintained, because of the fact that the set or deformation of the springs, made during the adjustment thereof, tends 'to be gradually lost by spontaneous return of the spring toward the formation which it had prior to the adjusting deformation thereof. It will be seen that, in my improved construction, adjustments of the contacts made by bending or deformation of the U-strips 42 are definitelyand positively maintained by the adjustingscrews 44, and are not subject to variation except by deliberate and intentional re-adjustment of said screws, and that by means of said adjusting-screws 44 a. pluralityrof the contacts may be easily ali'n'ed with each other, or adjusted to'j cooperative relation with the respective contact-.springs toproducethe desired gap at .open position, orV the desired. contact-pressure at closed position, ,s

or tilted laterallyV to aline the, faces of the .l

contacts `with the ends of the respective contact-springs. The' U-strips 42 Vform a connection of high Velectrical conductivity be- 'I tween .the con-tacts` 4l'jand the respective binding-posts 22, and the conductivity of the connection is notl altered -by adjustments inY position of the contacts.

It will be noted also thatlas the contact-hV springs 38 are straightiiat pieces of metal, L the construction thereof will requireno deformation of the flat sheets in Awhich, the

material used in the springs iscustomarily formed originally, and consequentlyV therekv willLbe no tendency forfthe occurrence of spontaneousvariation in `theform of said sprin'gsBS, whereby the relations of thecontacts might be altered after adjustment v l j vthereof had been made. s Now, having described my invention, what I claim and desire to secure byLetters Patent l. In a relay A of the class described, the

' combination with an electromagnet and its arma-ture, of means for supporting said armature for movement toward and from the electromagnet, comprising a laterallyrflexible member secured at one end to the armature and at the other end to a frame-member xedly associated with the electromagnet, said laterally flexible member 'extending i substantially parallel with but spaced laterally from the line of traction of the electromagnet.

2. In a relay of the classdescribed, the combination with an electromagnet, armature, and frame, of a laterally flexible armature-supporting member Aextending substantially parallel with but spaced laterally from the line of tractionv of the electromagnet, Yone end of said laterally flexible member being secured to the frame and the other end thereof secured to the armature and supporting the same, whereby movements of the armature toward and from the electromagnet are enabled by lateral bending of said armature supporting means.

3. In a structure as set means for adjusting the relation of the armature-supporting member to the frame in a. direction parallel with the line of magnetic traction, whereby to vary the air-gapbetween the armature and the poles of the electro-- magnet. Y v 4 4. In arelay of the class described, a frame, an electromagnet fixedly mounted thereon and having adjacent poles, an armature positioned in operative relation to saidpoles, laterally flexible means extending forth in claim 2,

substantially parallel with thelineof traction of saidelectromagnet and spac'ed laterally from said axis, said laterally flexible means secured'at one endto the frame and secured at the other end to the armature whereby to support the same for movement toward and' from the magnet polesand sul stantially about an axis spaced from` said poles and from` the axis of attraction.

. 5. In a relay of the class described, a baseplate, an electromagnet mounted thereon and having pole-pieces projecting beneath the saine', a bracket carried :by the base-plate and extending downwardly therefrom and spaced from the pole-pieces, flat springs secured kto the lower portion of said bracket andextending upwardly therefrom, an armature disposed b'cneatl1=tlie pole-pieces and having its rear edge secured to the 'upper' portions of said springs and supported thereon, contact-fingers secured to saidarmature and extending forwardly therefrom, stationary contacts supported upon thebase-plate,

V6. In-a relay of the class described, theV combination with a movable armature, and

contact-fingers carried by said armature,A of a contact-spring carried by each of said n'gers, r a contact engageable by said spring, and an j adjustable support for said Contact eolnpris- 'I ing a resilient U-strip havingV the contact' aflix'ed `to one leg thereof and the otherleg affixed to 'a support, and an adjustingscrew for Varying the'spread of the U-strip atthe openend thereof; Y

7.' A struct-ure asset forth -in claim 6,'including an adjusting-screw for each side ol the U-strip, whereby to separately adjust'the sides thereof and effect a lateral tilting of the supported Contact.

' DAVID C. BETTISON. 

